feat: P0 backup system (WAL+snapshot+restore+verify), monitoring stack, admin health API

scripts/backup/setup-wal.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+set -euo pipefail
+
+BACKUP_DIR="/opt/memento/backups"
+WAL_DIR="$BACKUP_DIR/wal"
+PG_CONTAINER="memento-postgres"
+PG_USER="${POSTGRES_USER:-memento}"
+PG_DB="${POSTGRES_DB:-memento}"
+PG_PASSWORD="${POSTGRES_PASSWORD:-}"
+LOG_FILE="$BACKUP_DIR/backup.log"
+
+mkdir -p "$WAL_DIR"
+
+log() {
+  echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1" | tee -a "$LOG_FILE"
+}
+
+log "=== Setting up WAL archiving ==="
+
+docker exec "$PG_CONTAINER" psql -U "$PG_USER" -d "$PG_DB" -c "
+ALTER SYSTEM SET wal_level = replica;
+ALTER SYSTEM SET archive_mode = on;
+ALTER SYSTEM SET archive_command = 'cp %p /var/lib/postgresql/backups/wal/%f';
+ALTER SYSTEM SET max_wal_senders = 3;
+ALTER SYSTEM SET wal_keep_size = '1GB';
+"
+
+docker exec "$PG_CONTAINER" mkdir -p /var/lib/postgresql/backups/wal
+
+docker exec "$PG_CONTAINER" psql -U "$PG_USER" -d "$PG_DB" -c "SELECT pg_reload_conf();"
+
+log "WAL archiving enabled. Archives stored in /var/lib/postgresql/backups/wal/"
+
+WAL_COUNT=$(docker exec "$PG_CONTAINER" ls /var/lib/postgresql/backups/wal/ 2>/dev/null | wc -l)
+log "Existing WAL segments: $WAL_COUNT"